First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020

SEC source: 0000860413-25-000100 · wk-form4_1748977156.xml · nonDerivative · entry 1

Scott James R. Jr · CIK 0001675872 · Director · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 78,545

F1 · shares: Shares issuable upon vesting of restricted stock units granted to the reporting person pursuant to the Registrant's 2023 Equity and Incentive Plan. The restricted stock units vest on June 1, 2026, subject to the reporting person's provision of continuous service to the Registrant through the earlier of the applicable vesting date or the date of the Registrant's [next] annual stockholder meeting.

SEC source: 0000860413-25-000074 · wk-form4_1748625714.xml · nonDerivative · entry 6

Scott James R. Jr · CIK 0001675872 · Director · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 75,599

F3 · shares: Disposition to the issuer of issuer securities in payment of minimum required withholding taxes due upon vesting of restricted stock units.

SEC source: 0000860413-25-000074 · wk-form4_1748625714.xml · nonDerivative · entry 5

Scott James R. Jr · CIK 0001675872 · Director · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 77,345

F3 · shares: Disposition to the issuer of issuer securities in payment of minimum required withholding taxes due upon vesting of restricted stock units.

SEC source: 0000860413-25-000074 · wk-form4_1748625714.xml · nonDerivative · entry 4

Scott James R. Jr · CIK 0001675872 · Director · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 77,368

F4 · shares: Shares issuable upon vesting of restricted stock units granted to the reporting person pursuant to the Registrant's Equity and Incentive Plan, which units are scheduled to vest in three equal annual installments beginning on March 15, 2026, subject to the reporting person's continued employment through each applicable vesting date.

SEC source: 0001493152-24-047565 · ownership.xml · nonDerivative · entry 1

Scott James R. Jr · CIK 0001675872 · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 75,387

SEC source: 0000860413-25-000074 · wk-form4_1748625714.xml · nonDerivative · entry 3

Scott James R. Jr · CIK 0001675872 · Director · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 76,155

F3 · shares: Disposition to the issuer of issuer securities in payment of minimum required withholding taxes due upon vesting of restricted stock units.

SEC source: 0000860413-25-000074 · wk-form4_1748625714.xml · nonDerivative · entry 2

Scott James R. Jr · CIK 0001675872 · Director · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 76,178

F2 · shares: Shares issuable upon vesting of restricted stock units granted to the reporting person pursuant to the Registrant's Equity and Incentive Plan, which units are scheduled to vest in three equal annual installments beginning on March 15, 2025, subject to the reporting person's continued employment through each applicable vesting date.

SEC source: 0000860413-25-000074 · wk-form4_1748625714.xml · nonDerivative · entry 1

Scott James R. Jr · CIK 0001675872 · Director · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 75,579

F1 · shares: Shares issuable upon vesting of restricted stock units granted to the reporting person pursuant to the Registrant's Equity and Incentive Plan, which units are scheduled to vest in three equal annual installments beginning on March 15, 2024, subject to the reporting person's continued employment through each applicable vesting date.

SEC source: 0001493152-22-031525 · ownership.xml · nonDerivative · entry 1

Scott James R. Jr · CIK 0001675872 · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 81,454

F1 · price: The price reported in column 4 is a weighted average price. The shares sold on 11/10/2022 were sold in multiple transactions at prices ranging from $ 46.25 to $ 46.305. The reporting person undertakes to provide to First Interstate BancSystem, Inc., any security holder of First Interstate BancSystem, Inc.. or the staff of the Securities and Exchange Commission, upon, request, the full information regarding the number of shares sold at each separate price within the ranges set forth above.

SEC source: 0001493152-22-029964 · ownership.xml · nonDerivative · entry 2

Scott James R. Jr · CIK 0001675872 · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 85,306

SEC source: 0001493152-22-029964 · ownership.xml · nonDerivative · entry 1

Scott James R. Jr · CIK 0001675872 · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 90,306

F1 · price: The price reported in column 4 is a weighted average price. The shares sold on 10/28/22 were sold in multiple transactions at prices ranging from $ 45.00 to 45.007. The reporting person undertakes to provide to First Interstate BancSystem, Inc., any security holder of First Interstate BancSystem, Inc.. or the staff of the Securities and Exchange Commission, upon, request, the full information regarding the number of shares sold at each separate price within the ranges set forth above.

SEC source: 0001493152-22-023136 · ownership.xml · nonDerivative · entry 1

Scott James R. Jr · CIK 0001675872 · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100,436

F1 · price: The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $ 42.00 to 42.04. The reporting person undertakes to provide to First Interstate BancSystem, Inc., any security holder of First Interstate BancSystem, Inc.. or the staff of the Securities and Exchange Commission, upon, request, the full information regarding the number of shares sold at each separate price within the ranges set forth above.

SEC source: 0001493152-22-022386 · ownership.xml · nonDerivative · entry 1

Scott James R. Jr · CIK 0001675872 · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 102,936

F1 · price: The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $ 41.00 to 41.04. The reporting person undertakes to provide to First Interstate BancSystem, Inc., any security holder of First Interstate BancSystem, Inc.. or the staff of the Securities and Exchange Commission, upon, request, the full information regarding the number of shares sold at each separate price within the ranges set forth above.

SEC source: 0000899243-22-012682 · doc4.xml · derivative · entry 2

Scott James R. Jr · CIK 0001675872 · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · see footnote

Disclosed balance after: 0

Underlying: Class A Common Stock · 149,137 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Pursuant to the Issuer's articles of incorporation, because the aggregate number of shares of Class B Common Stock constituted less than twenty percent (20%) of the aggregate number of shares of the Issuer's issued and outstanding common stock as of March 25, 2022, the record date of the Issuer's annual meeting of shareholders, each outstanding share of Class B Common Stock was automatically converted into one share of Class A Common Stock.

F1 · kind: Pursuant to the Issuer's articles of incorporation, because the aggregate number of shares of Class B Common Stock constituted less than twenty percent (20%) of the aggregate number of shares of the Issuer's issued and outstanding common stock as of March 25, 2022, the record date of the Issuer's annual meeting of shareholders, each outstanding share of Class B Common Stock was automatically converted into one share of Class A Common Stock.

F1 · derivative.exercise_date: Pursuant to the Issuer's articles of incorporation, because the aggregate number of shares of Class B Common Stock constituted less than twenty percent (20%) of the aggregate number of shares of the Issuer's issued and outstanding common stock as of March 25, 2022, the record date of the Issuer's annual meeting of shareholders, each outstanding share of Class B Common Stock was automatically converted into one share of Class A Common Stock.

F1 · derivative.expiration_date: Pursuant to the Issuer's articles of incorporation, because the aggregate number of shares of Class B Common Stock constituted less than twenty percent (20%) of the aggregate number of shares of the Issuer's issued and outstanding common stock as of March 25, 2022, the record date of the Issuer's annual meeting of shareholders, each outstanding share of Class B Common Stock was automatically converted into one share of Class A Common Stock.

F3 · ownership.nature: Composed of 105,436 shares held of record by James R. Scott Jr., 25,642 shares held of record by First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020, 25,642 shares held of record by First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020.

SEC source: 0000899243-22-012682 · doc4.xml · nonDerivative · entry 1

Scott James R. Jr · CIK 0001675872 · 10% owner

First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910215 · 10% owner

First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020 · CIK 0001910352 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · see footnote

Disclosed balance after: 156,720

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: Pursuant to the Issuer's articles of incorporation, because the aggregate number of shares of Class B Common Stock constituted less than twenty percent (20%) of the aggregate number of shares of the Issuer's issued and outstanding common stock as of March 25, 2022, the record date of the Issuer's annual meeting of shareholders, each outstanding share of Class B Common Stock was automatically converted into one share of Class A Common Stock.

F1 · price: Pursuant to the Issuer's articles of incorporation, because the aggregate number of shares of Class B Common Stock constituted less than twenty percent (20%) of the aggregate number of shares of the Issuer's issued and outstanding common stock as of March 25, 2022, the record date of the Issuer's annual meeting of shareholders, each outstanding share of Class B Common Stock was automatically converted into one share of Class A Common Stock.

F2 · balance_after: As a result of certain agreements entered into by and among the reporting persons, the Issuer, and certain other stockholders of the Issuer, the reporting persons may be deemed members of a group with the other signatories thereto and may be deemed to share beneficial ownership of the securities reported herein. Each of the reporting persons disclaims beneficial ownership of any such securities, except to the extent of its pecuniary interest therein. The reporting persons expect to file future Forms 4 and 5, if any, together with James R. Scott Jr.

F3 · ownership.nature: Composed of 105,436 shares held of record by James R. Scott Jr., 25,642 shares held of record by First Interstate Bank TTEE for Dana S Andersson GST Exempt Trust No 1 Dtd 12/11/2020, 25,642 shares held of record by First Interstate Bank TTEE for James R Scott Jr. GST Exempt Trust No 1 Dtd 12/11/2020.